o . ..... 'i . . 'III "When you drill for gas north of the Arctic Circle, the way we're doing here at Canada's Mackenzie Delta, you expect a lot of problems," says Bob Toole, drilling superintendent for Gulf "But this one's a real fooler It's a freezing unit.. Even at 52 0 below zero, we need it to keep the ground around the wellhead frozen. :;. .. ... .. 4 , G,,",,'f 'C "At temperatures as low as this, you have to lnvent new ways to do almost everything" "'" '",.. " "The problem is that when the drilling mud comes up from the bottom of the hole, maybe a mile down, it's hot enough to melt the permafrost that's hold-- ing up the whole rig. "If the permafrost melted, the hole would get bigger and bigger, and the operation would have to come to a halt. "Our freezer keeps the top thirty feet of the casing around the drill pipe at temperatures below freezing, so that doesn't happen. "This country is probably one of the toughest spots on earth to drill for natural gas.. But we're drilling the wells. We're meeting the challenge:' \ .... \, ......---... ... Gul pe pie: ..K.eti ng the challen e. Gulf Oil Corporation >;;. eft t '.right. Bob Toole, Jacob Kuhoktak 1 oustabout, and the freexer. ."., %.